Program self-regulating control system



E F, GEIGER April 14, 1 931.

PROGRAM SELF REGULATTNG CONTROL SYSTEM Filed May 1927 3 Sheets-Sheet l E. F. GEIGER April 14, 1931.

PROGRAM SELF REGULATTNG CONTROL SYSTEM F1 led May 5 Sheets-Sheet 2 3 WW To a 5%M 837% fltto'muu April 14, 1931. E. F. GEIGER 1,800,381

PROGRAM SELF RBGULATING CONTROL SYSTEM Filed May 2, 927 3 Sheets-Sheet 3 WWZW Patented Apr. 14, 1931 UNITED STATES PATENT OFFICE EDWARD F. GEIGER, OF BINGHAMTON, NEW YORK, ASSIGNOR T INTERNATIONAL TIME RECORDING COMPANY OF NEW YO 'I'ION OF NEW YORK BK, OF ENDICOTT, NEW YORK, A CORPORA- PROGRAM SELF-REGULATING CONTROL SYSTEM Applicationfiled May 2, 1927. Serial No. 188,166.

co-pending. patent application Serial No.

153,279, now Patent Feb. 4, 1930.

In a synchronizing clock' system of the self-regulating type in which a plurality of secondary-units are to be operated in accordance with a primary or master clock by minute impulses transmitted by the master clock, the impulses are automatically transmitted through a pair of connected wires, commonly called A and B wires, to which the secondary clocks are connected selectively, in accordance with contacts controlled by the Wsition of the secondary clocks themselves.

Number 1,7 45 ,924, dated hen impulses are being transmitted over both wires, the secondary clocks will he stepped ahead one unit, commonly one minute, each time an impulse is received irrespective of the position of the controlling contacts. During a certain interval, called the synchronizing period, one of the main wires, such as the B wire is automatically disconnected from the master clock and impulses are transmitted over the remaining wire, or A wire only. Under such conditions, the secondary clocks which are connected to the A wire, are stepped ahead'in accordance with the minute impulses from the master clock, while the secondary clocks, connected to the B wire remain stationary.

The selective contacts in the secondary clocks are controlled by cams in accordancev with the time indication of the secondaries to disconnect the clock from the A wire and connect it with the B wire when the clock reaches a given position, which is commonly chosen as the 59th minute position. If the master clock is designed to open the B wire during the last 15 minutes of each hour, should any secondary unit be fast, its contact would operate as soon as the clock indi cated the 59th minute, to connect the clock with the B wire. The B wire being opened by the master clock, no impulses are received and the clock remains stationary until the master clock itself registers the even hour period when impulses are again transmitted through both wires and both clocks step ahead in synchronism.

In order to synchronize a clock which is running slow, mechanism is associated with the master clock which will impress a series of rapid impulses upon the A wire during the last minute of the hour. Any secondary unit which is slow will then be stepped ahead in accordance with the rapid impulses until the selectivecontacts are actuated to disconnect the clock from the A wire and connect it to the B wire which occurs when the secondary registers the fifty-ninth minute. On the even hour minute impulses are again sent over the B wire and the secondary again startes oil? in synchronism with the master clock.

A practice widely used in manufacturing shops is operating time recording machines in such a manner as to record the time of the working period only. Such machines are generally known as job time recorders, and in order to accomplish this it is necessary to stop the advance of the time mechanism of the machine during such periods that the shop is not operating, such as the lunch hour.

As an example, a job time recorder is equipped with an hour wheel having hour type reading from 0 to 22 so that one complete revolution of this wheel will require 23 hours consecutive operating. At 7 a. m., or starting time, the recorder will register 0. At 12 noon the recorder will register 5. As there is a lunch period from 12 to 1, when the shop suspends operations, the recorder is caused to cease its further operation during that time so that when it is again started at l p. 111., when the shop resumes operation, it still registers 5. Thus in 24 hours the clock will have operated only during 23 hours and the hour type wheel will have made a complete revolution returning to O at 7 a. m.

Inasmuch as the corrective controls' are operated between the 59th minute and the even hour to bring all outlying secondaries in phase with their nearest hour. position, should they be slightly slow or fast, these the even hour position after the corrections were completed and were still at the same place when the next succeeding hourly correction was made.

If conditions are such as to require job time recorders being stopped at the even hour and started again during some part of the even hour, then the minute type wheel will necessarily be running out of phase with the minute wheels of those time units in other parts of the system which have not been stopped. Under such circumstances the min ute and hour wheels in the job time recorders will be at some other position than at the hour when the corrective impulses are initiated by the master clock. Therefore, if these corrective influences should operate on the job time recorders they would have a tendency to bring them back again into the same hourly phase relationship with that of all the other time units, which is not desired. Program devices are utilized to connect the time recorders to and disconnect them from their operating circuits and the program device also functions to prevent these corrective means from influencing the job time recorders when necessary. As an example, a job time recorder having a 0 to 22 hour wheel which makes one revolution from 0 to O in 23 hours running time is set to start with 0 at 7 a. m. At 12 111., having operated 5 hours, it records 5. A lunch hour of 45 minutes, during which time the operathe even hour, will show an apparent relation of being 15 minutes in advance of the others so that when the master clock initiates correcting electrical impulses on the hour, it would attempt to bring the ob time recorders back in line to its nearest even hour were it not for the fact that the program device had operated to prevent this. The purpose of the job time recorder being to record the actual number of working hours during which the operator has worked on a given job, it must of course maintain its out of phase relationship with the master clock for the remainder of the working day.

As the hour and minute wheel of the job time recorder is not now running synchronously with the hour and minute wheels of the other regular time units, it would not be 0 at 7 a. m. when the next working period is started. It is, therefore, necessary, to stop this job time recorder sometime during the night when the shop is closed, for a period of 15 minutes, thus making a total of one hours time eliminated by the job time recorder during the day. The type wheel, as previously explained, being so arranged as to \make one revolution during this 23 hours of actual running will, therefore, be at its zero position at 7 a. m. The program device, previously mentioned, controls the stopping and starting time of the job time recorder circuit as well as determining whether or not the corrections shall be applied to the job time recorder circuit.

The principal object of the invention is to provide a synchronizing system for secondary units which operate on a schedule. Another object of the invention is to provide a synchronizing system for secondary units which are controlled from a program device and more specifically to control such a synchronizing system from theprogram device.

Still another object of the invention is to make provision forcontrolling the synchronizing system independently of the normal operating system so that the synchronizing system may be rendered inoperative when a normal outof phase relationship is established between the master unit and the secondary units. 1

Still another object of the invention is to make provision for effecting automatic synchronization between a master unit and its secondaries as long as an in-phase relationship should normally exist between them and to make provision for automatically discontinuing the synchronizing action when a normal out-of-phase relationship is established between the master and its secondaries.

Still another object of the invention is to provide for removing the control of a synchronizing system from the master unit to permit of great flexibility of synchronizing control for the secondary.

These and other objects which will be hereinafter pointed out will be clear from the following detailed description which should be read in connection with the accompanying drawings in which:

Fig. 1 is a diagrammatical representation of a time unit system according to the invention and Figs. 2 and 3 are similar representations of modifications of the system.

Referring to Fig. 1 of the drawing one modification of the invention is shown. A master clock illustrated diagrammatically at 9 controls the minute stepping impulses for drivin continuously operating secondary units, indicated in the present instance as a program device 28, and minute stepping impulses for intermittently operating secondary units indicated as a job time recorder 40.

The synchronizing control of the program device operates direct from the master clock, as usual, while that of the time recorder is governed by the program device. The minute stepping impulses for both devices are initiated by contacts 25 which are closed once each minute by a cam 8 mounted on a suitable shaft of the master clock. Cams 6 and 7 are mounted on the minute hand arbor of the master clock and the latter effects closure of contacts 30 atthe beginning of the synchronizing period and opening of them at the end of this period to control opening of the B line circuits. The contacts 31 are closed by the. cam 6 for the period of one half minute during the last minute of each synchronizing period, that is during the th minute of each hour. These latter contacts are in series with a pair of contacts 5, one of which is fixed and the other of which is mounted on the detent of a deadbeat escapement 4 operating from a sixty beat master clock pendulum making sixty oscillations a minute or one a second. The eseapement causes the contacts 5 to close every two seconds and while the contacts 31 are closed for one half minute during the last minute of each synchronizing period the contacts 5 initiate fifteen fast impulses on the A line for the purpose of synchronizing any secondary units which are running slow.

Lines 11 and 12 are the A and B lines, respectively, for the secondary units represented by the program device. Each secondary unit connected in multiple to these lines has a cam 13 associated with it which actuates contacts 14 and 15, causing contacts 14 to close and contacts 15 to open when the secondary reaches the 59th minute registration of each hour thus shifting the stepping magnet 27 of the secondary from the A wire 11 to the B line 12. At a later time designation, usually fifteen minutes past the hour, the reverse action occurs shifting the magnet back to the A line.

The system for periodically energizing the A and B lines 11 and 12 for driving the secondary time units connected thereto will now be described. In the drawing only one such secondary unit has been illustrated and this in the form of a program device for controlling a j ob time recorder. It will be understood that any number of such units may be connected to the lines in parallel to the one shown and that these units may be either simple'program devices, simple secondary clocks or secondary clocks with program devices attached. The cam 8 closes contacts 25 once each minute and energizes magnets 23 and 24 through the following circuit: From one ter minal of battery 10 through wires 21 and 22 and magnets 23 and 24, in parallel with each other, to contacts 25 and thence to the other terminal of the battery. The periodic energizations of magnet 24 close its relay contacts 26 and supply minute stepping impulses to the line 11 from battery 10, these minute impulses continuing as long as the master clock is in operation. The A line 11 is connected to the B line 12 through back contacts 28 of relay 29 and the minute stepping impulses will likewise be supplied to the B line as long as rela coil 29 is deenergized. Coil 29 is control ed by cam contacts 30 which are normally held open by the cam 7 but permitted to close during the synchronizing period. lVhe-n these contacts close the relay magnet 29 is energized through a circuit extending from battery 10 through wire 21, coil 29, contacts 30 and back to the battery. The B wire 12, then, receives minute stepping impulses during the non-synchronizing portion of each hour but receives no impulses during the. synchronizing period which usually extends from the 45th to the 60th minute.

During half of the 59th minute of each hour cam (S closes its associated contacts 31 whereupon during this half minute closure of the two second contacts 5 effect fifteen rapid cnergizations of relay coil 32, the circuit extending as follows: From positive terminal of battery 10 through wires 21 and 22 to relay coil 32, thence through contacts 5 and 31 to contacts 230, closed during the synchronizing period as already explained, and thence to the negative terminal of the battery. The relay contacts 33 close for each cnergization of the. coil 32 and apply a series of two second impulses to the front contact 34 of relay 29. During the synchronizing period as already explained the relay 29 is energized attracting its armature against its front contact 34 and applying the series of rapid impulses to the. A line 11. Briefly summarizing the operation, then, the A line 11 receives minute impulses constantly and receives a series of rapid impulses during the last minute of each hour, while the B line 12 receives minute impulses except during the synchronizing period when it receives no impulses at all.

The secondary time unit is provided with a stepping'magnet 27 which has one terminal grounded and the other-terminal selectively connected to the A or B wires 11 and 12 through contacts 14 and 15. These contacts are controlled by a cam 13 driven by the secondary unit and arranged to close contacts 15 to connect the magnet 27 to A line 11 when the unit registers anywhere from fifteen minutes to fifty-nine minutes after the even hour and to close contacts 14 to connect the magnet to the B wire 12 when the unit registers anywhere from one minute before the hour to fifteen minutes after the hour. The contacts 14 are arranged to open when the contacts 15 close and vice versa so that the stepping magnet is connected to only one line at a time.

Now, if the secondary is running fast at the beginning of a synchronizing period, as soon as it registers 59 minutes after the hour its contacts 14 close and shift. its stepping.

stationary until the B wire receives its first stepping impulse on the next even hour whereupon it again starts off in synchronism with the master. If the secondary is running slow at the beginning of a synchronizing period its contacts 15 remain closed connecting it to the A line. During the 59th minute its stepping magnet 27 receives the rapid two second impulses stepping the unit ahead rapidly until it registers 59 minutesafter the hour whereupon the cam 13 closes contacts 14 shifting the magnet to the B wire 12 and at the first impulse over this wire on the even hour the unit again starts off in synchronism with the master. At any time outside of the synchronizing period, of course, minute impulses are transmitted over both the A and B wires and it is immaterial to which the stepping magnet is connected.

A job time recorder which is designed to eliminate periods of time as previously explained is represented at 40. The driving mechanism of this device is of the usual form in secondary time units being provided with the usual stepping magnet 57 and a cam 41 with coacting contacts 42 and 43 corresponding in structure and function to those on the program device. This recorder is controlled and synchronized from lines 56 and 59 which correspond to the lines 11 and 12 for the program device and of which 56 is the A line and 59 is the B line. These lines are supplied with stepping and synchronizing impulses in a manner similar to that in which lines 11 and 12 are supplied but in this case the impulses are controlled from the program device operating in conjunction with the master clock as will now be explained. a

The program device 28 is of the well known type shown in my copending application, Serial No. 671,686, filed Oct. 30, 1923 and is provided with a disc 44 in which pins may be placed to close a pair of contacts 45 at any desired times, the contacts being arranged to remain closed for substantially one minute whenever a pin in the disc actuates them. These contacts control a make and break device consisting of a stepping magnet 47, a ratchet 50 with an attached cam 51 and a pair of contacts 52. At each energization of magnet 47 a pawl 49 mounted on the end of armature 48 effects partial rotation of ratchet 50 and attached cam 51. At each actuation of the cam it moves an angular distance sufficient to bring an insulated piece carried by one of the contacts 52 to the top of the next adjacent dwell 53 if it happens to be resting in one of the notches between dwells or to bring it into the next notch if it happens to be resting on a raised dwell at the time of cam actuation. When the insulated piece is on a dwell the contacts 52 are closed and when the piece is in a notch the contacts are open, fromwhich it willbe understood that the contacts are successively closure of these contacts has no effect on the make and break magnet 47 unless the conacts 45 are closed at the same time from which it follows that the magnet will be energized once whenever a pin on disc 44 closes contacts 45. Thus one pin on the disc Will effect opening of the contacts 52, the next pin will effect closure of these contacts and so on. Thecontacts 52 control the stepping impulsessupplied to the A and B lines 56 and 59 to drive the time recorder 40. At each minute energization of relay 23 with contacts 52 closed, the relay 54 will be energized closing its contacts 55, the circuit extending from battery 10, through contacts 46 and 52 to relay coil 54 and thence through ground re turn back to the battery. The periodic energizations of relay 54 supply the usual minute stepping impulses to the A and B lines 56 and 59 the circuit extending from positive terminal of battery 10 to contacts 55 and thence to A wire 56 direct, and to B wire 59 through back contact 58 of relay 63 as'long as the latter is deenergized. The mechanism thus far described explains how the usual minute stepping impulses are supplied to the A and B lines 56 and 59 and as impulses are supplied as long as contacts 52 are closed and are not supplied as long as these contacts are open it is obvious that the recorder can be cut out of operation atany time by suitably placing a pin in disc 44 and can be out back into operation at any desired time by properly placing a second pin in the disc.

The synchronization of the time recorder is effected under control of a second disc 60 on the program device which by means of pins in its periphery is adapted to close congized through a circuit extending from bat:

tery 10 through wire 62. relay coil 63 and contacts 61 to ground. Back contact 58 of the relay is then opened and front contact 64 closed. The opening of front contact 58 opens the B line 59 so that it receives no impulses of any sort while the closing of contact 64 connects the A line 56 to the A line 11 whereupon the line 56 receives the fast two second impulses from the line 11 during the 59th minute of the hour. The cam 41 of the timerecorder is designed to open contacts 43 and close contacts 42 when the recorder registers the even hour instead of on the 59th minute as in the case of the other constantly operating secondary units. During the operating periods of the time recorder, then, that is while the contacts 52 are closed it will be stepped ahead with the .sponding to 12:00 oclock it drives and synchronizes in the usual manner. At this time its contacts 42 closeshifting its driving magnet to the B line 59 which is then opened by the relay 63. The recorder, now having stopped on the B line, receives no more impulses until 1:00 oclock as the contacts 52 have now been opened under control of the program. The minute impulse and fast two second impulses which are supplied to the A line 59 from the line 11 during this inactive period have no effect on the recorder as the latter has been shifted to the B line and its contacts 43 are open. At 1:00 oclock the following pin on the program disc 44 again closes contacts 45 whereupon the magnet 47 of the make and break device is energized by the next minute impulse from relay contacts 46 stepping the cam 51- and again closing the contacts 52. The recorder thus starts off again with the master clock getting its first stepping impulse at 1:00 oclock and continues to drive and synchronize until another pin in program disc 44 closes contacts 45.

When irregular or fractional hours of elimination are required such as, for example, when a recess or lunch period extends from 12: 00 m. to 12: 45 p. m. it is necessary to suppress the synchronizing action on the time recorder after its first normally inactive period of the day as from this time on it has a nor mal out of phase relationship with the master clock which must not be disturbed. In this case the pins on the program disc 60 are arranged so that they will close contacts 61during the forenoon, in the usual manner to effect synchronizing of the recorder but no pins are placed on the disc which will close these contacts after noon. After the first recess period when the relay 63 is not energized, contacts 58 remain closed connecting the B line 59 to the Aline 56 and both lines receive minute impulses whenever the contacts 52 are closed. The time recorder will thus receive one driving impulse each minute regardless of the position of its cam 41.

Various conditions and problems in manufacturing make modifications of the time system such as just has been explained, necessary. There are instances in large industries where different departments operate under different schedules and because of these different schedules, it is frequently desirable to run separate circuits of time units, and have one circuit synchronize at a different time than another. As an example; an industry having several departments requires, because of its number of employees and its limited capacity for handling them at their noon hour, that their dismissals for this noon hour he staggered in ten minute variation. For example, department A starts its noon hour at 12 oclock; department B starts its noon hour at 11 50; department G, starts its noon hour at 11:40. Under such conditions where a large body of men are ringing out at 10 minutes before the hour, it would be desirable to have the corrections of the system occur just previous to this dismissal period rather than on the hour, for it is obvious that if the systemis fast or slow, and is not to be corrected until the hourly position, than all registrations at 10 minutes before the hour will show this error. It is with this object in view that been marked with the same reference numerals as in Fig. 1 while those whose functions differ have been given distinctive numerals. The actuators of the escape verge 4, circuit closers 5, 25, 30 and 31, cams 6, 7 and 8 in the master clock are identical with the previous disclosure as are also the operations of the control relays 24, 29, 32, with their associated contacts. The program 28 is operated and regulated in the same manner as just previously explained and the functioning of the associated contacts 14 and 15, its cam 13 and its driving magnet 27 are identical. The program machine 28 operating on the lines 11 and 12 is regulated and corrected directly from the master clock and it controls relays 24, 29 and 32 as previously described, the correcting period occurring between the 45th minute and the 60th minute of each hour, while the rapid impulses for stepping those units on the line ahead, that are slow at the time, occur between the 59th and 60th minute.

Recorder 40 represents any secondary unit operating on a continuous schedule and on a circuit where it is undesirable to use the same period of time for correcting them as used on the other circuits A and B just described. For the purpose of more clearly explaining the invention, let it be assumed that it is desired to have the correcting period occur between 25 minutes and 10 minutes before the hour. The minute impulse contacts 25 are closed once each minute by means of the cam 8 thereby closing a circuit from the negative terminal 16 of the battery 10 through contacts 25, magnet coil 23 wires 22 and 21 to the positive battery terminal 20.

The magnet 23 being energized attracts its armature, closing relay contact 46 thus closing a circuit from positive battery terminal 20, line 21, contact 46 to the A line 72 of the secondary unit 40. The B line 59 of this unit is connected to the A line when necessary by relay 63 exactly as in the previous modification. The A and B lines 72 and 59 drive the unit 40 through its stepping magnet 57 under control of the cam contacts 42 and 43 as before. I

Groups of pins are placed in the periphery of the program disc 60 at intervals such that the first pin of a group coacts with program contacts 61 closing them at 25 minutes before each hour and the successive pins the group keep said contacts closed for a period of 15 minutes the last pin passing and allowing program contact 61 to open at 10 minutes before the hour.

The cam 41 in the recorder 40 is set to cause its coacting contacts 42 to close at 10 minutes before the hour and likewise cause the contacts 43 to open.

When program contacts 61 close at 25 minutes before the hour the magnet coil 63 is energized through the following circuit positive battery terminal 20, lines 70 and 71, contacts 61, relay magnet coil 63 to the ground return circuit. The energization of relay magnet 63 attracts its armature closing contacts 64 and breaking contacts 58 thus making B line 59 dead so that impulses sent by the closing of relay contact 46 can no longer come over this line but can only travel over A line 7 2.

Assuming recorder 40 is 5 minutes fast when the recorder registers 20 minutes before the hOlJJI' contact 43 will have been] closed, the true time now being 25 minutes before the hour, contact 58 will break and stay broken for 15 minutes. Relay contact 46 closing every minute continues to send out electric impulses thereby engaging recorder drive magnet 57 through contact- 43 thus stepping the recorder wheel ahead each time until the recorder registers 10 minutes before the hour when contact 43 breaks and contact 42 makes. The driving magnet 57 is now connected to line 59 which is dead and the recorder stops advancing. In five minutes the program machine 28 will have reached the position of 10 minutes before the hour at which time program contact 61 opens deenergizing the relay magnet 63 thus allowing its armature to drop closin contact 58 and breaking contact 64. The ollowing minute impulse caused by the momentary closing of contact 46 each minute will now cause current to flow through its contacts, contact 58, line 59, contact 42, recorder drive magnet 57 to the ground. The recorder is now stepped along once each minute having been corrected with the master clock control.

Twenty minutes aftercontact 42 closes, it

relay contact 46 closes on the 11th minute, a

circuit is completed as follows: From the positive battery terminal to relay contact 46, program contact 45, rapid impulse relay magnet 73 to the ground. At the opening of relay contact 46 breaking this circuit the program machine steps forward breaking program contact 45 and deenergizing rapid impulse relay 74 which starts this relay operating. The rapid relay 74 is a well known type of circuit interrupter which introduces tension into a spring when its magnet 73 is energized and permits this tension to dissipate itself upon its deenergization by driving an escapement through a gear train thus causing cam 75 to revolve. The revolving of this cam opens and closes its coacting contact 76 and is so timed through the escapement to cause this contact to close at about two second intervals, the energy in the spring driving said cam being sufiicient to cause the contact 76 to close about 15 times. Each time that the rapid impulse relay contact 76 closes, a circuit is established from the positive battery terminal 20 through line 70, relay magnet coil 77, contacts 76 to the ground, thus energizing relay magnet 77 and causing its armature to close its contact 78. As the relay contact 78 makes its series of rapid closures it completes a circuit from positive battery terminal 20, relay contact 78, relay contact 64 now closed to A line 72.

Thus any recorder which is slow, that is, whose contacts 43 are closed, is rapidly stepped up to time utilizing as many of the impulses as required. In the example cited the recorder is 5 minutes slow so that six impulses would advance the clock to ten minutes before the hour at which time contact 43 breaks and contact 42 closes thus stopping further progress of the recorder. Immediately following the series ofrapid impulses initiated by the rapid impulse relay, the master clock sends out its impulse for the 50th minute advancing the program 28 at its break causing its contact 61 to open and deenergizing relay 63 thus opening its contact 64 and closing contact 58. The recorder, the pro- I ingly the correction of the recorder is accomplished.

Many industries and institutions, required to increase their time equipment to take care of expansion, desire to keep up with the trend of the times. andpurchase the latest and most improved devices, yet are not in a position to discard the old equipment then in use. In order to operate time equipment having improvements such as self regulating features, it is necessary to provide special means in conjunction with the old system. It is therefore the purpose of a third modification of the invention to provide means for operating self-regulating time units from a master clock and control of the well known minute impulse type.

Fig. 3 shows diagrammatically a wiring arrangement in which the cam 8 revolves once a minute, causing its coacting contacts to close once each minute for a duration of 2 seconds at each closing. The closure of these contacts establishes a circuit from the negative grounded terminal 16 of the battery 25 10 through contacts 25, magnet coil 24 to the positive battery terminal 20. The energization of magnet coil 24 each minute attracts its armature thus closing relay contact 26 each minute thereby closing a circuit through the program stepping magnet 27 as follows:

From positive battery terminal 20, relay contact 26, program drive magnet 27 to the ground thence to grounded negative battery terminal 16. The program 28 having no 85 cam and contacts for self correcting as in the previous instances operates from the master clock as a straight minute impulse secondary unit Well known in the art. The self regulating circuit on which is shown one time recorder operates through the control of the program in identically the same manner as the recorder of the same reference character described in connection with Fig. 2 of this application which is briefly summarized as follows:

Program contacts 61 close for 15 minutes each hour as selected by placing a series of pins in the periphery of program discs 60. The closing of these contacts energizes relay coil 63 to break its contact 58 thus making line 59 dead so that if the recorder is fast and gets to the correcting period ahead of time it will be thrown by its contacts onto the dead line and will stay still until the relay contact 58 is closed again at the proper time through the opening of program contacts 61. The rapid impulse relay 74 is set in motion by means of pins set in the periphery of disc 44 at ,the proper time as previousl explained. Contacts 76 open and close whille relay contact 64 is still made thereby delivering rapid impulses to all of the secondary units which are behind and still have their contacts 43 closed connecting them to 65 the A line 56, rapidly stepping each up to the point Where their contacts 42 close placing their driving magnets in circuit with the B line 59. As before described the contact 76 rapidly opens and closes relay contacts 78 through the energization and deenergization of its magnet coil 77. This relay transmits the rapid impulses direct to those units that are lagging at the time and the minute impulses are transmitted by the relay contacts 46 the actuating coil 23 of which is energized by the closing each minute of the relay 24. Normally relay contact 58 being closed at all times other than during the correcting period permits the impulses from relay contacts 46 to travel over both A and B lines 56 and 59 thus resuming the advance of the secondary units on those lines.

What I claim is:

1. In a time controlled system a master unit, a program device, a secondary unit, means controlled by the master unit for op erating the same and means controlled by said program device to render said secondary unit operative or inoperative during selected periods and means controlled by said program device for maintaining synchronism between said master and secondary units.

' 2. In a time controlled system a master unit, a secondary unit comprising a program device controlled by said master unit and means for maintaining synchronism between said master unit and said secondary unit, an additional secondary unit controlled by said master unit and means controlled by said program device for controlling the actuation of said additional unit and for maintaining synchronism between the additional unit and the master unit during its periods of actuation.

3. In a time controlled system a master unit, a program device and a secondary unit controlled thereby for a schedule involving normally active and normally inactive periods, means controlled by said master unit for operating said secondary unit, means for maintaining synchronism between said secondary unit and said master unit and means for interrupting the operation of said synchronizing means during the normal inactive periods of the secondary unit.

4. In a time controlled system, a master unit, a program device and a secondary unit controlled thereby for a schedule involving periods during which said secondary unit is normally in phase with said master unit and periods during which said secondary is normally out of phase with said master unit, means controlled by said master unit for operating said secondary unit, means for maintaining synchronism between said secondary and master and means for interrupting the operation of said synchronizing means during the out of phase periods.

5. ha time controlled system, a master unit, a program device and a secondary unit,

means controlled by said master unit for driving the secondary and means controlled by said program device for effecting driving of the secondary unit according to a schedule involving normally active periods and normalinactive periods, means controlled conjfointly by said program device and said secondary unit for periodically interrupting the 10 operation of the latter during its active period when it runs fast as compared to the master and means controlled conjointly by the program device and the secondary unit for periodically driving the latter at a rate 15, flaster than the master unit when it runs s ow.

6. In a time controlled system a master unit, a program device and a secondary unit, means controlled by said master unit for driving the secondary and means controlled by said program device for effecting driving of the secondary according to a schedule involving periods in which said secondary and master are normally in phase and periods in which said secondary and master are normally out of phase, means controlled conjointly by said program device and said secondary for periodically interrupting the driving operation of the latter when it runs fast and for periodically driving it at a faster rate than the master when it runs slow and means controlled by the program for interrupting the operation of said last named means during the normally out-of phase periods of the sec- F ondary.

7 In a time controlled system, a master clock, a pair of transmission lines extending therefrom'for driving secondary units on an uninterrupted schedule and a pair of transmission lines extending therefrom for driving secondary units on an interrupted schedule, means controlled by said master clock for initiating a succession of normal stepping impulses for both pairs of lines, and a secondary unit connected to said first named pair of lines comprising means for periodically interrupting the stepping impulses on one of the lines of said second named pair, and a secondary unit comprising selective means for connecting itself selectively to one or the other of said second pair of transmission lines.

8. In a time controlled system, a master clock, a pair of transmission lines extending therefrom for driving secondary units and means controlled by said master clock for initiating a series of normal stepping impulses, means for connecting both of said lines to and disconnecting them from said last named means according to a predetermined schedule and means for periodically disconnecting one only of said lines from the source of stepping impulses during its normally connected periods.

9. In a time controlled system, a master 7 for initiating a series of normal stepping impulses and a second mechanism for periodically initiating a series of impulses of higher frequency than the stepping impulses, said first mechanism only being controlled by the master clock, means for connecting and disconnecting the lines to the first mechanism according to a predetermined schedule and means for connecting one only of said lines to said second mechanism.

11. In a time controlled system, a master clock and means controlled thereby for operating secondary units, a secondary unit and means for connecting it to and disconnecting it from said first named means according to a predetermined schedule providing for oper ating periods in which the secondary is normally in phase with the master and periods in which the secondary is normally out of phase with said master, means for synchronizing said secondary with said master during its operating periods and means for disabling said synchronizing. means during normal out of phase operating periods.

12. In a time controlled system, a master unit with means controlled thereby to emit periodic impulses, a secondary unit having operating meanscontrolled by the periodic impulses from the master unit, a program device for controlling the operating means of the secondary unit to render the same alter-' nately responsive and non-responsive to the impulses from the master unit during selected periods and means controlled by the program device for maintaining synchronism between the master and secondaryunits during the operating periods of the latter.

In testimony whereof I hereto affix my signature. 7

EDWARD F. GEIGER. 

